"The British variant has about 20 mutations, including several that affect how the virus locks onto human cells and infects them. These mutations may allow the variant to replicate and transmit more efficiently, said Muge Cevik, an infectious disease expert at the University of St. Andrews in Scotland and a scientific adviser to the British government.
But the estimate of greater transmissibility — British officials said the variant was as much as 70 percent more transmissible — is based on modeling and has not been confirmed in lab experiments, Dr. Cevik added."
“Over all, I think we need to have a little bit more experimental data,” she said. “We can’t entirely rule out the fact that some of this transmissibility data might be related to human behavior.”
Officials in Britain and South Africa claim new variants are more easily transmitted. There’s a lot more to the story, scientists say.
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